It is proposed to continue a study of the structure and function of retinal neurones of Rana. Studies of horizontal cells and receptor telodendria will be completed during the initial grant period. This renewal proposal concerns bipolar and amacrine cells. Procedures include intracellular recording to establish basic receptive field properties and HRP injectioned and morphometric studies by light and electron microscopy of injected cells. These data will be correlated with quantitative data from Golgi preparations and serial light and electron microscopy of standard preparations. For bipolars, the study will correlate cell function with dendritic fine structure, identified receptor contacts, general morphology, level of branching and the fine structure and distribution of contacts on telodendria. For amacrine cells, cell function will be correlated with process pattern and extent, fine structure and distribution of contacts. Catecholamine and Indoleamine containing cells of the inner retina will be characterized by light and electron microscopy using formaldehyde induced histofluorescence and selective degeneration procedures. The morphology of these cells will be correlated with the results of the Golgi and HRP studies.